Read the file in chunks, unpack each chunk, check for patterns in the last chunk plus the current chunk (if the patterns may extend over chunk boundaries), pack and print half the modified data to a second file, assign the other half to last chunk, rinse and repeat. There should be no need to ever have more than a few K of data in memory.

In reply to Re: Out of memory problems by TedPride
in thread Out of memory problems by tperdue

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